Microstrip Filters for RF/Microwave Applications
JIA-SHENG HONG
M. J. LANCASTER
A WILEY-INTERSCIENCE PUBLICATION
JOHN WILEY & SONS, INC.
NEW YORK / CHICHESTER / WEINHEIM / BRISBANE / SINGAPORE / TORONTO
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Copyright (C) 2001 by John Wiley & Sons, Inc. All rights reserved.
ISBN 0-471-22161-9
This title is also available in print as ISBN 0-471-38877-7.
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Contents
Preface
1.Introduction
2.Network Analysis
2.1Network Variables
2.2Scattering Parameters
2.3Short-Circuit Admittance Parameters
2.4Open-Circuit Impedance Parameters
2.5 ABCD Parameters
2.6Transmission Line Networks
2.7Network Connections
2.8Network Parameter Conversions
2.9Symmetrical Network Analysis
2.10Multi-Port Networks
2.11Equivalent and Dual Networks
2.12Multi-Mode Networks
References
3.Basic Concepts and Theories of Filters
3.1Transfer Functions
3.1.1General Definitions
3.1.2The Poles and Zeros on the Complex Plane
3.1.3Butterworth (Maximally Flat) Response
3.1.4Chebyshev Response
3.1.5Elliptic Function Response
3.1.6Gaussian (Maximally Flat Group-Delay) Response
3.1.7All-Pass Response
3.2Lowpass Prototype Filters and Elements
3.2.1Butterworth Lowpass Prototype Filters
3.2.2Chebyshev Lowpass Prototype Filters
3.2.3Elliptic Function Lowpass Prototype Filters
3.2.4Gaussian Lowpass Prototype Filters
3.2.5All-Pass Lowpass Prototype Filters
3.3Frequency and Element Transformations
3.3.1Lowpass Transformation
3.3.2Highpass Transformation
3.3.3Bandpass Transformation
3.3.4Bandstop Transformation
3.4Immittance Inverters
3.4.1Definition of Immittance, Impedance and Admittance Inverters
3.4.2Filters with Immittance Inverters
3.4.3Practical Realization of Immittance Inverters
3.5Richards¡¯Transformation and Kuroda Identities
3.5.1Richards¡¯Transformation
3.5.2Kuroda Identities
3.5.3Coupled-Line Equivalent Circuits
3.6Dissipation and Unloaded Quality Factor
3.6.1Unloaded Quality Factors of Lossy Reactive Elements
3.6.2Dissipation Effects on Lowpass and Highpass Filters
3.6.3Dissipation Effects on Bandpass and Bandstop Filters
References
4. Transmission Lines and Components
4.1 Microstrip Lines
4.1.1Microstrip Structure
4.1.2Waves in Microstrip
4.1.3Quasi-TEM Approximation
4.1.4Effective Dielectric Constant and Characteristic Impedance
4.1.5Guided Wavelength, Propagation Constant, Phase
4.1.5 Velocity, and Electrical Length
4.1.6Synthesis of W/h
4.1.7Effect of Strip Thickness
4.1.8Dispersion in Microstrip
4.1.9Microstrip Losses
4.1.10Effect of Enclosure
4.1.11Surface Waves and Higher-Order Modes
4.2Coupled Lines
4.2.1Even- and Odd-Mode Capacitances
4.2.2Even- and Odd-Mode Characteristic Impedances and Effective
4.1.5 Dielectric Constants
4.2.3More Accurate Design Equations
4.3Discontinuities and Components
4.3.1Microstrip Discontinuities
4.3.2Microstrip Components
4.3.3Loss Considerations for Microstrip Resonators
4.4Other Types of Microstrip Lines
References
5.Lowpass and Bandpass Filters
5.1Lowpass Filters
5.1.1Stepped-Impedance L-C Ladder Type Lowpass Filters
5.1.2L-C Ladder Type of Lowpass Filters using Open-Circuited Stubs
5.1.3Semilumped Lowpass Filters Having Finite-Frequency
5.1.3 Attenuation Poles
5.2Bandpass Filters
5.2.1End-Coupled, Half-Wavelength Resonator Filters
5.2.2Parallel-Coupled, Half-Wavelength Resonator Filters
5.2.3Hairpin-Line Bandpass Filters
5.2.4Interdigital Bandpass Filters
5.2.5Combline Filters
5.2.6Pseudocombline Filters
5.2.7Stub Bandpass Filters
References
6. Highpass and Bandstop Filters
6.1Highpass Filters
6.1.1Quasilumped Highpass Filters
6.1.2Optimum Distributed Highpass Filters
6.2Bandstop Filters
6.2.1Narrow-Band Bandstop Filters
6.2.2Bandstop Filters with Open-Circuited Stubs
6.2.3Optimum Bandstop Filters
6.2.4Bandstop Filters for RF Chokes
References
7. Advanced Materials and Technologies
7.1Superconducting Filters
7.1.1Superconducting Materials
7.1.2Complex Conductivity of Superconductors
7.1.3Penetration Depth of Superconductors
7.1.4Surface Impedance of Superconductors
7.1.5Nonlinearity of Superconductors
7.1.6Substrates for Superconductors
7.1.7HTS Microstrip Filters
7.1.8High-Power HTS Filters
7.2Ferroelectric Tunable Filters
7.2.1Ferroelectric Materials
7.2.2Dielectric Properties
7.2.3Tunable Microstrip Filters
7.3Micromachined Filters
7.3.1MEMS and Micromachining
7.3.2Micromachined Microstrip Filters
7.4MMIC Filters
7.4.1MMIC Technology
7.4.2MMIC Microstrip Filters
7.5Active Filters
7.5.1Active Filter Methodologies
7.5.2Active Microstrip Filters
7.6Photonic Bandgap (PBG) Filters
7.6.1PBG Structures
7.6.2PBG Microstrip Filters
7.7Low-Temperature Cofired Ceramic (LTCC) Filters
7.7.1LTCC Technology
7.7.2Miniaturized LTCC Filters
References
8. Coupled Resonator Circuits
8.1General Coupling Matrix for Coupled-Resonator Filters
8.1.1Loop Equation Formulation
8.1.2Node Equation Formulation
8.1.3General Coupling Matrix
8.2General Theory of Couplings
8.2.1Synchronously Tuned Coupled-Resonator Circuits
8.2.2Asynchronously Tuned Coupled-Resonator Circuits
8.3General Formulation for Extracting Coupling Coefficient k
8.4Formulation for Extracting External Quality Factor Qe
8.4.1Singly Loaded Resonator
8.4.2Doubly Loaded Resonator
8.5Numerical Examples
8.5.1Extracting k (Synchronous Tuning)
8.5.2Extracting k (Asynchronous Tuning)
8.5.3Extracting Qe
References
9. CAD for Low-Cost and High-Volume Production
9.1Computer-Aided Design Tools
9.2Computer-Aided Analysis
9.2.1Circuit Analysis
9.2.2Electromagnetic Simulation
9.2.3Artificial Neural Network Modeling
9.3 Optimization
9.3.1Basic Concepts
9.3.2Objective Functions for Filter Optimization
9.3.3One-Dimensional Optimization
9.3.4Gradient Methods for Optimization
9.3.5Direct Search Optimization
9.3.6Optimization Strategies Involving EM Simulations
9.4Filter Synthesis by Optimization
9.4.1General Description
9.4.2Synthesis of a Quasielliptic Function Filter by Optimization
9.4.3Synthesis of an Asynchronously Tuned Filter by Optimization
9.4.4Synthesis of a UMTS Filter by Optimization
9.5 CAD Examples
References
10.Advanced RF/Microwave Filters
10.1Selective Filters with a Single Pair of Transmission Zeros
10.1.1Filter Characteristics
10.1.2Filter Synthesis
10.1.3Filter Analysis
10.1.4Microstrip Filter Realization
10.2Cascaded Quadruplet (CQ) Filters
10.2.1Microstrip CQ Filters
10.2.2Design Example
10.3Trisection and Cascaded Trisection (CT) Filters
10.3.1Characteristics of CT Filters
10.3.2Trisection Filters
10.3.3Microstrip Trisection Filters
10.3.4Microstrip CT Filters
10.4Advanced Filters with Transmission Line Inserted Inverters
10.4.1Characteristics of Transmission Line Inserted Inverters
10.4.2Filtering Characteristics with Transmission Line Inserted Inverters
10.4.3General Transmission Line Filter
10.5Linear Phase Filters
10.5.1Prototype of Linear Phase Filter
10.5.2Microstrip Linear Phase Bandpass Filters
10.6Extract Pole Filters
10.6.1Extracted Pole Synthesis Procedure
10.6.2Synthesis Example
10.6.3Microstrip Extracted Pole Bandpass Filters
10.7Canonical Filters
10.7.1General Coupling Structure
10.7.2Elliptic Function/Selective Linear Phase Canonical Filters
References
11. Compact Filters and Filter Miniaturization
11.1Ladder Line Filters
11.1.1Ladder Microstrip Line
11.1.2Ladder Microstrip Line Resonators and Filters
11.2Pseudointerdigital Line Filters
11.2.1Filtering Structure
11.2.2Pseudointerdigital Resonators and Filters
11.3Miniature Open-Loop and Hairpin Resonator Filters
11.4Slow-Wave Resonator Filters
11.4.1Capacitively Loaded Transmission Line Resonator
11.4.2End-Coupled Slow-Wave Resonator Filters
11.4.3Slow-Wave, Open-Loop Resonator Filters
11.5Miniature Dual-Mode Resonator Filters
11.5.1Microstrip Dual-Mode Resonators
11.5.2Miniaturized Dual-Mode Resonator Filters
11.6Multilayer Filters
11.6.1Wider-Band Multilayer Filters
11.6.2Narrow-Band Multilayer Filters
11.7Lumped-Element Filters
11.8Miniaturized Filters Using High Dielectric Constant Substrates
References
12. Case Study for Mobile Communications Applications
12.1HTS Subsystems and RF Modules for Mobile Base Stations
12.2HTS Microstrip Duplexers
12.2.1Duplexer Principle
` 12.2.2 Duplexer Design
12.2.3Duplexer Fabrication and Test
12.3Preselect HTS Microstrip Bandpass Filters
12.3.1Design Considerations
12.3.2Design of the Preselect Filter
12.3.3Sensitivity Analysis
12.3.4Evaluation of Quality Factor
12.3.5Filter Fabrication and Test
References
Appendix:Useful Constants and Data
Index